In order to alleviate the pressure of the surge in the high-speed data services on high-cost wireless network, mobile operators urgently need effective means to offload the low-value data services from the wireless network as soon as possible.
In the indoor access scene, a typical offloading and network construction solution is as shown in FIG. 1, wherein the structure of this network is based on the flat architecture, the Femto Node B ends the air interface, and for offloading data stream, Network Address Translation (NAT) technology is used to process the data of the Non-Access Stratum (NAS) and then sends it to Gi interface. This solution is mainly used in 2/3Gnetwork, but conditionally restricted in the LTE network.
In this network structure, a Femto Node B is configured with offloading identification mechanism and a Gi interface protocol stack, so that the low-value business data can be identified directly in the Femto Node Band sent to the relatively low-cost fixed network transmission, while the high-value business data can be sent to the traditional wireless network transmission channel in which high-value business data can achieve refined management and service.
The protocol stack model of the offloading data stream is as shown in FIG. 2. This kind of network construction solution can quickly and easily deploy offloading strategy, but the problem is that the mobility is not high. Once the User Equipment (UE) is moved out from the initial accessed Femto Node B, the link of the offloading data stream must be disconnected and then reconnected. The reason is that: a UE is connected to the Internet with the Internet Protocol (IP) address IPue, when the message sent by the UE passes through Femto Node B 1, it will be replaced by the IP address IPnb1 of the Femto Node B 1 by the NAT module, while in fact the IP address linked to the Internet is IPnb1; when the UE moves to another Femto Node B 2, the NAT module of Femto Node B 2 can use the IP address IPnb2 of Femto Node B 2 at this time to replace IPue. Thus, the IP address interacting with the Internet is changed. For the Internet server, the peer IP of the same connection cannot be changed, because the connection is not the same when the peer IP address is changed. Therefore, there is a problem of the poor mobility in the current offloading solution.